Prognosis
The disease appears to be a progressive one. They started having problems when they were four years old. By the time they had reached the age of nine, they were having difficulty walking and needed help from frames to help them walk around. Their muscles have been slowly deteriorating with each year they grow older. Having this disease also makes the twins' hands shake, which makes it difficult for them to do simple things like writing. The disease affects the twins' nerves and causes them to make involuntary muscle movements, for example, their hands shaking.
The extent of the disease is still unknown because the two women are only 18, but so far nothing about their disease has affected their brains or any part of their personalities. Doctors do not know if the disease is fatal, and if it is, when it will come to that point. Also there is a chance that if the twins have children, they could pass their disease onto their offspring.
Read more about this topic: Fields' Disease